Method for measuring coaxiality of rotating part of model pump turbine

Abstract

The invention relates to the technical field of water turbine installation, and discloses a method for measuring the coaxiality of a rotating part of a model pump turbine, and the method comprises the following steps: 1, calibrating the coaxiality of a rotating wheel and a coupling flange combination body; 2, putting the combined body into a tool device, connecting the combined body with the hydrostatic bearing, and reserving a measurement space; and 3, coaxiality calibration is conducted on the lower comb tooth ring face, the lower ring outer ring sealing face, the upper crown outer ring sealing face and the upper comb tooth ring face of the rotating wheel. And the phenomenon that the upper crown of the runner is rubbed with the sealing surface and the comb tooth surface of the top cover is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of water turbine installation, and in particular to a method for measuring the coaxiality of a rotating part of a model water pump water turbine. Background Art

[0002] The accuracy of the turbine runner coaxiality is crucial to the operation of the turbine. If the coaxiality deviation is too large, the runner vibration will increase, which may cause the vibration of the unit or bearing, further causing the expansion of the gap, damaging the turbine generator, reducing the hydrodynamic performance of the turbine, and affecting the power generation efficiency.

[0003] Chinese patent document CN119146837A discloses an auxiliary measuring tool for the coaxiality of a turbine runner and a measuring method thereof, wherein the auxiliary measuring tool for the coaxiality of a turbine runner comprises a fastener, a support, a piano wire, a weight, an oil drum and an inner diameter micrometer. The present invention places the turbine runner on a horizontal plane, and adjusts the level of the turbine runner to within 0.02 mm / m; the turbine main shaft is connected to the turbine runner through a fastener, and the verticality of the turbine main shaft is adjusted to within 0.02 mm / m; a support is installed on the journal of the turbine main shaft symmetrically in the XY direction, one end of the piano wire is fixedly wound around the top of the support, and a weight is provided at the other end of the piano wire, and the weight is suspended in the oil drum; the shortest distance from the journal of the turbine main shaft to the piano wire, the shortest distance from the upper crown of the turbine runner to the piano wire, and the shortest distance from the lower ring of the turbine runner to the piano wire are measured by an inner diameter micrometer.

[0004] At present, when doing model experiments, Figure 1 As shown in the figure, when installing the pump turbine model device, first hoist the volute, water guide mechanism and hydrostatic bearing together to the test bench to measure the water torque, place a dial indicator at the lower bearing interface of the hydrostatic bearing to complete the coaxiality measurement of the top cover and the bottom ring sealing ring surface, then hang the runner and coupling flange combination to the lower bearing interface of the hydrostatic bearing, and then use the dial indicator to measure the coaxiality of the rotating part. When conducting the model test, the sealing surface and comb tooth surface of the runner crown and the top cover are prone to mutual scratching. Summary of the invention

[0005] In order to solve the technical problem that the sealing surface and comb tooth surface of the runner crown and the top cover are prone to mutual scratching, the present invention provides a method for measuring the coaxiality of the rotating part of a model water pump turbine, comprising the following steps: Step 1, calibrate the coaxiality of the combination of the runner and the coupling flange; Step 2: Place the combined body into the tooling device and connect it to the hydrostatic bearing, leaving space for measurement; Step 3: calibrate the coaxiality of the lower comb tooth annular surface of the runner, the lower ring outer ring sealing surface, the upper crown outer ring sealing surface and the upper comb tooth annular surface.

[0006] Preferably, in step 3, the coaxiality of the lower comb tooth annular surface of the rotating wheel, the lower ring outer ring sealing surface, the upper crown outer ring sealing surface and the upper comb tooth annular surface is calibrated.

[0007] Preferably, in step 2, the hydrostatic bearing is mounted on the top of the fixture and the end is inserted into the fixture, and the combination is connected to the end of the hydrostatic bearing.

[0008] Preferably, the tooling device comprises an upper ring plate, a lower ring plate and a supporting rib plate, the upper ring plate and the lower ring plate are connected via a plurality of supporting rib plates, and a space for dial indicator measurement is formed between the upper ring plate and the lower ring plate.

[0009] In order to facilitate the installation and measurement of the dial indicator, the size of the upper ring plate is smaller than that of the lower ring plate, and the supporting rib plate is a rib plate with an arc.

[0010] In order to facilitate the installation of the combined body and the connection between the combined body and the hydrostatic bearing, through holes are provided in the middle of the upper ring plate and the lower ring plate.

[0011] If the coaxiality of step 3 cannot be met, in order to improve the measurement accuracy of the water torque, in step 4, when the coaxiality of the runner is not met, the runner is disassembled, and a runner pad is installed between the runner and the hydrostatic bearing, and a thin copper sheet is padded on the upper end surface of the runner pad, and then step 3 is repeated again.

[0012] Furthermore, in step 5, when the coaxiality of the runner is not satisfied, the coaxiality of the assembly of the runner and the coupling flange is readjusted, and steps 3 and 4 are repeated.

[0013] The present invention has the following beneficial effects: 1. In the prior art, due to the interference between the top cover and the bottom ring, the outer ring sealing surface of the lower ring of the runner, the outer ring sealing surface of the upper crown, and the upper comb tooth ring surface cannot be calibrated for coaxiality using a dial indicator. Only the coaxiality of the comb tooth ring surface of the runner can be calibrated, so the accuracy of the coaxiality of the runner, the coupling flange, and the hydrostatic bearing cannot be guaranteed. The present invention pre-installs the rotating part of the model water pump turbine and measures the coaxiality. The coaxiality of the runner, the coupling flange, and the hydrostatic bearing are pre-installed and confirmed in advance by a tooling device. Afterwards, they are installed on the test bench. The sealing surface and comb tooth surface of the upper crown of the runner and the top cover do not scratch each other, so that the runner rotates smoothly without friction hindrance and does not introduce friction torque, thereby ensuring the subsequent measurement value of the runner water torque on the test bench. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic diagram of the runner water torque on the test bench; Figure 2 Schematic diagram of step 1 in an embodiment of the present invention; Figure 3 Schematic diagram of step 2 in an embodiment of the present invention; Figure 4 Schematic diagram of step 3 in an embodiment of the present invention; Figure 5 Schematic diagram of step 4 in an embodiment of the present invention; Figure 6 Schematic diagram of step 5 and step 6 in an embodiment of the present invention; Figure 7 A schematic diagram of a tooling device in an embodiment of the present invention; Figure 8 for Figure 7 Top view of the . DETAILED DESCRIPTION

[0015] The following is further described in detail through specific implementation methods: Those skilled in the art will know that a hydrostatic bearing is a sliding bearing that uses a pressure pump to force a pressurized lubricant into the tiny gap between the bearing and the shaft. The working principle of a hydrostatic bearing is to form a lubricating film between the bearing and the shaft through the pressurized lubricant, thereby reducing friction and wear. Specifically, a hydrostatic bearing has oil cavities on its inner circumferential surface, and lubricants are pumped into these oil cavities through a pressure pump. When the bearing is subjected to a load, the lubricant in the oil cavity will generate a pressure difference, thereby lifting the shaft and surrounding it in the oil cavity, forming liquid lubrication.

[0016] The figure marks in the drawings of the specification include: runner 1, coupling flange 2, tooling device 3, upper ring plate 301, lower ring plate 302, supporting rib plate 303, through hole 304, hydrostatic bearing 4, runner gasket 5, lower comb tooth annular surface 6, lower ring outer ring sealing surface 7, upper crown outer ring sealing surface 8, upper comb tooth annular surface 9, test bench 10, bottom ring 11, top cover 12, runner upper crown 13, dial indicator 14.

[0017] Example 1 like Figure 2-8 As shown, a method for measuring the coaxiality of the rotating part of a model water pump turbine comprises the following steps: Step 1: pre-assemble the runner 1 and the coupling flange 2 into a joint body, and calibrate the coaxiality of the joint body using a dial indicator; Step 2: Place the combined body into the space formed between the upper ring plate 301 and the lower ring plate 302 of the tooling device 3; Step 3, the hydrostatic bearing 4 is installed on the top of the tooling device 3 and the end is inserted into the space of the tooling device 3; Step 4, connecting the combined body to the end of the hydrostatic bearing 4; Step 5, slowly rotate the runner 1, and use the dial indicator 14 to calibrate the coaxiality of the lower comb tooth surface 6, the lower ring outer ring sealing surface 7, the upper crown outer ring sealing surface 8 and the upper comb tooth surface 9 of the runner 1 in the tooling device 3; Step 6, if the coaxiality deviation cannot be controlled within ±0.05mm, disassemble the runner 1, install a runner pad 5 between the runner 1 and the hydrostatic bearing 4, insert a thin copper sheet into the upper end surface of the runner pad 5, slowly rotate the runner 1, and use the dial indicator 14 to calibrate the coaxiality of the lower comb tooth ring surface 6, the lower ring outer ring sealing surface 7, the upper crown outer ring sealing surface 8 and the upper comb tooth ring surface 9 of the runner 1 in the tooling device 3; Step 7, if the coaxiality deviation cannot be controlled within ±0.05mm, readjust the coaxiality of the assembly of the runner 1 and the coupling flange 2 by adjusting the connecting bolts of the runner 1 and the coupling flange 2, and repeat steps 5 and 6 until the coaxiality of the lower comb tooth annular surface 6 of the runner 1, the lower ring outer ring sealing surface 7, the upper crown outer ring sealing surface 8 and the upper comb tooth annular surface 9 is controlled within ±0.05mm; Step 8: Install the runner 1, coupling flange 2 and hydrostatic bearing 4 that have been calibrated for coaxiality on the test bench 10 to perform a model experiment.

[0018] The tooling device 3 includes an upper ring plate 301, a lower ring plate 302 and a supporting rib plate 303. The upper ring plate 301 and the lower ring plate 302 are connected by multiple supporting rib plates 303. A space for measurement by a dial indicator 14 is formed between the upper ring plate 301 and the lower ring plate 302. The size of the upper ring plate 301 is smaller than that of the lower ring plate 302, and the supporting rib plate 303 is a rib plate with an arc.

[0019] The middle parts of the upper ring plate 301 and the lower ring plate 302 are both provided with through holes 304 to facilitate the installation of the combined body and the connection of the combined body with the hydrostatic bearing 4 .

[0020] The above is only an embodiment of the present invention. The common sense such as the known specific structure and characteristics in the scheme is not described in detail here. The ordinary technicians in the relevant field know all the common technical knowledge in the technical field of the invention before the application date or priority date, can obtain all the existing technologies in the field, and have the ability to apply the conventional experimental means before that date. The ordinary technicians in the relevant field can improve and implement this scheme in combination with their own abilities under the enlightenment given by this application. Some typical known structures or known methods should not become obstacles for ordinary technicians in the relevant field to implement this application. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, which will not affect the effect of the implementation of the present invention and the practicality of the patent. The protection scope required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A method for measuring the coaxiality of the rotating part of a model pump turbine, characterized in that: The following steps are involved: Step 1, calibrate the coaxiality of the runner and the coupling flange combination; Step 2: Place the combined body into the tooling device and connect it to the hydrostatic bearing, leaving space for measurement; Step 3: Calibrate the coaxiality of the rotating wheel.

2. The method for measuring the coaxiality of the rotating part of a model pump turbine according to claim 1, characterized in that: In step 3, the coaxiality of the lower comb tooth annular surface of the runner, the lower ring outer ring sealing surface, the upper crown outer ring sealing surface and the upper comb tooth annular surface is calibrated.

3. The method for measuring the coaxiality of the rotating part of a model water pump turbine according to claim 2, characterized in that: In step 2, the hydrostatic bearing is installed on the top of the fixture and the end is inserted into the fixture, and the combination is connected to the end of the hydrostatic bearing.

4. The method for measuring the coaxiality of the rotating part of a model pump turbine according to claim 3, characterized in that: The tooling device comprises an upper ring plate, a lower ring plate and a supporting rib plate. The upper ring plate and the lower ring plate are connected by a plurality of supporting rib plates. A space for dial indicator measurement is formed between the upper ring plate and the lower ring plate.

5. The method for measuring the coaxiality of the rotating part of a model pump turbine according to claim 4, characterized in that: The size of the upper ring plate is smaller than that of the lower ring plate, and the supporting rib plate is a rib plate with an arc.

6. The method for measuring the coaxiality of the rotating part of a model pump turbine according to claim 5, characterized in that: The middle parts of the upper ring plate and the lower ring plate are both provided with through holes.

7. The method for measuring the coaxiality of the rotating part of a model pump turbine according to claim 6, characterized in that: Step 4: When the coaxiality of the runner is not satisfied, disassemble the runner, install a runner pad between the runner and the hydrostatic bearing, pad the upper end surface of the runner pad with a thin copper sheet, and then repeat step 3 again.

8. The method for measuring the coaxiality of the rotating part of a model pump turbine according to claim 7, characterized in that: Step 5: If the coaxiality of the runner is not satisfactory, readjust the coaxiality of the assembly of the runner and the coupling flange, and repeat steps 3 and 4.

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